linux-kernel - Re: [PATCH v4 08/11] platform/x86: int3472: Add get_sensor_adev_and

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Mon, 1 Nov 2021 11:49:49 +0100
From:   Hans de Goede <hdegoede@...hat.com>
To:     Andy Shevchenko <andy.shevchenko@...il.com>
Cc:     "Rafael J . Wysocki" <rjw@...ysocki.net>,
        Mark Gross <markgross@...nel.org>,
        Andy Shevchenko <andy@...radead.org>,
        Wolfram Sang <wsa@...-dreams.de>,
        Mika Westerberg <mika.westerberg@...ux.intel.com>,
        Daniel Scally <djrscally@...il.com>,
        Laurent Pinchart <laurent.pinchart@...asonboard.com>,
        Mauro Carvalho Chehab <mchehab@...nel.org>,
        Liam Girdwood <lgirdwood@...il.com>,
        Mark Brown <broonie@...nel.org>,
        Michael Turquette <mturquette@...libre.com>,
        Stephen Boyd <sboyd@...nel.org>, Len Brown <lenb@...nel.org>,
        ACPI Devel Maling List <linux-acpi@...r.kernel.org>,
        Platform Driver <platform-driver-x86@...r.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
        linux-i2c <linux-i2c@...r.kernel.org>,
        Sakari Ailus <sakari.ailus@...ux.intel.com>,
        Kate Hsuan <hpa@...hat.com>,
        Linux Media Mailing List <linux-media@...r.kernel.org>,
        linux-clk <linux-clk@...r.kernel.org>
Subject: Re: [PATCH v4 08/11] platform/x86: int3472: Add
 get_sensor_adev_and_name() helper

Hi,

On 11/1/21 11:46, Andy Shevchenko wrote:
> On Mon, Nov 1, 2021 at 12:44 PM Andy Shevchenko
> <andy.shevchenko@...il.com> wrote:
>> On Mon, Nov 1, 2021 at 12:31 PM Hans de Goede <hdegoede@...hat.com> wrote:
>>> On 10/25/21 13:31, Andy Shevchenko wrote:
>>>> On Mon, Oct 25, 2021 at 12:42 PM Hans de Goede <hdegoede@...hat.com> wrote:
> 
> ...
> 
>>>>> +       if (ret == 0 && sensor_adev_ret)
>>>>> +               *sensor_adev_ret = sensor;
>>>>> +       else
>>>>> +               acpi_dev_put(sensor);
>>>>> +
>>>>> +       return ret;
> 
> ...
> 
>>>>        if (sensor_adev_ret)
>>>>                *sensor_adev_ret = sensor;
>>>>
>>>>        return 0;
>>>>
>>>> ?
>>>
>>> That misses an acpi_dev_put(sensor) when sensor_adev_ret == NULL.
>>
>> else
>>   acpi_dev_put(...);
>>
>> ?
> 
> Hmm... But then in the original code and with this proposal the
> acpi_dev_put() seems a bit strange to me.
> If we are fine (no error code returned) why would the caller (note
> _er_) go different paths?

We always need to get the dev to get the name, but some callers are
only interested in the name, so they pass NULL for sensor_adev_ret,
this helps to keep the code calling this clean, which is the whole
idea of having a helper for this.

Regards,

Hans